[llvm] [RISCV] Move performCombineVMergeAndVOps to RISCVVectorPeephole (PR #144076)

[Pengcheng Wang via llvm-commits]

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@@ -313,12 +313,12 @@ define i32 @test_nxv128i1(<vscale x 128 x i1> %x) {
 ; CHECK-NEXT:    vslidedown.vx v0, v6, a0
 ; CHECK-NEXT:    vsetvli a2, zero, e8, m1, ta, ma
 ; CHECK-NEXT:    vslidedown.vx v6, v7, a1
-; CHECK-NEXT:    vsetvli a1, zero, e32, m8, ta, ma
-; CHECK-NEXT:    vmerge.vim v8, v8, 1, v0
 ; CHECK-NEXT:    vsetvli a1, zero, e8, mf2, ta, ma
-; CHECK-NEXT:    vslidedown.vx v0, v7, a0
 ; CHECK-NEXT:    vslidedown.vx v5, v6, a0
+; CHECK-NEXT:    vslidedown.vx v4, v7, a0
 ; CHECK-NEXT:    vsetvli a0, zero, e32, m8, ta, mu
+; CHECK-NEXT:    vmerge.vim v8, v8, 1, v0
+; CHECK-NEXT:    vmv1r.v v0, v4
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wangpc-pp wrote:

Extra vmv.

https://github.com/llvm/llvm-project/pull/144076